The present invention relates generally to agricultural harvesters and, more specifically, to a harvester for removing crop from adjacent, closely spaced rows of plants.
Harvesters such as cotton pickers include row units having upright picker drums with spindles projecting into a row receiving area to remove cotton from a row of plants. Harvesting very narrowly spaced rows of cotton has been a continuing source of difficulty. Cotton picker units such as shown in commonly assigned U.S. Pat. No. 4,821,497 with picker drums supported in tandem on one side only of the row or nested row harvesting units as shown in U.S. Pat. No. 4,538,403 have provided row harvesting capability for some narrow row spacings, but the reduction has not been sufficient to accommodate very narrowly spaced rows of fifteen inches or less. In some areas the rows may be spaced as closely as twelve inches (30 cm), and harvesting with conventional row units can result in substantial adjacent row plant damage and cotton loss. Cotton strippers with comb style heads often are used for removing cotton from narrowly spaced plants, but such heads are relatively inefficient and fail to effectively separate cotton and trash.
In commonly assigned U.S. Pat. No. 6,212,864 filed May 28, 1999 and entitled NARROW ROW COTTON HARVESTER, a crop severing and conveying attachment is described for cutting a row of plants and moving the plants into an adjacent standing row prior to contact by a forward spindle drum. The cut plants intertwine with the standing row so the picking drums can remove cotton from both rows of plants. Although the attachment is capable of harvesting rows spaced apart fifteen inches or less, the cutter as shown therein is offset forwardly from the drums a considerable distance. The plants must be supported well to keep them upright as they move diagonally rearwardly into the adjacent standing row, and the system requires a relatively long belt conveyer and cutter drive system. The front of the attachment extends forwardly beyond the row unit thereby substantially increasing the operating length of the harvester.
In commonly assigned and copending U.S. application Ser. No. 09/436,330 filed Nov. 8, 1999 and entitled NARROW ROW HARVESTER, now U.S. Pat. No. 6,293,078, another narrow row system is described wherein the spindles of a forward drum provide both a lateral transporting function for a severed row of cotton and a cotton removal function for the severed row and an adjacent standing row of cotton. The lateral speed of the spindles is relatively high at point of contact with the severed plant. Therefore, the spindle transport function is aggressive and increases drum loading and wear. The high lateral speed of the spindles in the transport area also results in cotton plant disorientation and cotton loss. A rotating column, which is located ahead of the drum to assist in lateral movement of the severed plants, frequently wraps with plant material which is carried around with the column. A plant cutter which rotates at the same speed as the column to sever the cotton plants rotates too slowly for optimum cutting when the column is rotating at the desired plant transporting speed.
It is therefore an object of the present invention to provide an improved harvester row unit for harvesting crops planted in narrowly spaced rows. It is a further object to provide such a unit which overcomes most or all of the aforementioned problems.
It is a further object to provide such an improved harvester row unit for harvesting narrowly spaced rows of plants which severs plants offset from the row receiving area and moves the severed plants laterally into the row receiving area for contact with the spindles of a picker drum. It is another object to provide such a unit having reduced drum loading and wear compared to units wherein the spindles of the drum provide a substantial portion of the severed plant transverse conveying function.
It is another object of the present invention to provide an improved cotton picker row unit for simultaneously harvesting two narrowly spaced rows of cotton. It is a further object to provide such a row unit having a picking spindle drum for harvesting cotton from the two rows wherein the drum has at most only a minimal lateral transport function. It is yet another object to provide such row unit having improved cutting and lateral conveying characteristic and reduced drum loading and spindle wear.
It is still a further object to provide a cotton harvester row unit for harvesting narrowly spaced plants, and wherein the unit has an improved plant severing and transport system. It is another object to provide such a system having an improved drive arrangement which optimizes cutting efficiency and transport of severed plants into alignment with the spindle engagement area or crop removal zone of the unit.
It is another object to provide an improved harvester row unit capable of efficiently harvesting narrowly spaced cotton plants. It is a further object to provide such a unit particularly useful for harvesting rows of cotton plants spaced twelve to eighteen inches (30-45 cm.) apart. It is another object to provide such a unit for accommodating two adjacent rows of cotton wherein one of the rows is severed and moved laterally by feeder structure driven from the row unit drive structure. It is a further object to provide such a unit wherein the feed structure is synchronized with ground speed while the severing device is rotated at a higher speed.
A narrow row harvesting unit is described which is particularly useful for harvesting cotton plants in narrowly spaced rows. The crop removing portion of the unit includes a tandem spindle drum arrangement defining a main crop removing zone aligned with a standing row of cotton plants. A rotary knife offset ahead of the forward drum severs plants adjacent the row, and a feeder rotor or column with plant engaging projections rotates on a common axis with the rotary knife to gently direct the severed plants laterally between grid structure toward the crop removing zone and into the standing row prior to substantial engagement by the spindles on the forward drum. The rotary knife and feeder column are driven on the common axis from the row unit drive so the feeder column speed is synchronized with ground speed. The knife operates at a higher speed than the feeder to efficiently sever the plants and provide a clean cut. The feeder column includes fingers having a curved profile and projecting through vertically spaced bars of the grid structure to provide positive separation of the plant from the fingers. Plant carry-around by the feeder column is eliminated. Horizontal ribs located opposite the feeder column help keep the plants in contact with the fingers. The feeder column and rotary knife each are driven through a separate slip clutch for better protection. Kicker wheel structure located between the tandem drums moves plant material rearwardly in the zone. In one embodiment, the kicker wheel structure is located between the drums on the same side of the row as the drums to provide a compact package and facilitate kicker wheel drive.